In a multi-cell wireless communication system, a wireless transmit/receive unit (WTRU) receives TPC commands from more than one cell during handover. In one scheme, set forth under Third Generation Partnership Project (3GPP) standards, the WTRU conducts a reliability decision on each of the power control commands TPCi, where i=1, 2, . . . , N, (where N is greater than 1 and is the number of TPC commands from radio links of different radio link sets), and derives a combined TPC command as a function of all N soft symbol decisions Wi:Combined—TPC_cmd=γ(W1, W2, . . . WN);where Combined_TPC_cmd can take the values 1 (increase power) or −1 (decrease power). The function γ must fulfill the criteria as specified in the standards.
The 3GPP standards also require that if the N TPCi commands are random and uncorrelated, with equal probability of being transmitted as “0” or “1”, the probability that the output of γ is equal to 1 shall be greater than or equal to 1/(2N); and the probability that the output of γ is equal to −1 shall be greater than or equal to 0.5. The output of γ shall equal 1 if the TPC commands from all the radio link sets are reliably “1”, and the output of γ shall equal −1 if a TPC command from any of the radio link sets is reliably “0”.